A place for OOO utilities.
This is a public library, so we don't want hopelessly threerings-specific things in there (put those in the newly slimmed down threerings library). What we can do is rely on Guava, which is what keeps useful things out of samskivert and often pushes them into weird places like Narya.
What we can also do is use ooo-util to export the latest version of samskivert and Guava to all of our other projects. A project that relies on the latest snapshot of ooo-util can expect to have the latest snapshot of samskivert and Guava, and when either samskivert or Guava ships a versioned release, we'll ship a versioned release of ooo-util so that projects can bump to that release to obtain the latest transitive depends.
We should strongly resist the addition of additional depends to this library, unless they are indisputably useful to every single library and project in the whole wide world. Guava made that cut a long while back, and samskivert lingers with us like an embarrassing uncle, but I don't imagine another universally useful library is likely to come along in this decade. But if it does, we've got a place to put it.